The present invention relates to a dilator assembly adapted for percutaneous dilatational tracheostomy in a patient already having an endotracheal tube for ventilation, the dilator assembly comprising a dilator element having a wall and a proximal end part extending into a distal tip part via an intermediate part.
A tracheostomy is a surgical procedure to create an opening through the neck into the trachea. A tube is placed through the opening to provide an airway and to remove secretions from the lungs. This tube is called a tracheostomy tube or trach tube.
A tracheostomy is done in case of impaired respiratory function. This might be the case if for example a large object blocks the airway, the patient has an inherited abnormality of the larynx or trachea, has breathed in harmful material such as smoke, steam, or other toxic gases, suffers from diseases that otherwise affect breathing, e.g. severe neck or mouth injuries, or by paralysis of the muscles that affect swallowing. About 15% of the patients treated in intensive care units need a tracheostomy. The most common indications in this group are need for long-term ventilation, deteriorated pulmonary function and difficulties in weaning from respirator treatment.
Existing techniques for performing percutaneous tracheotomy procedure include making a curvilinear skin incision between sternal notch and cricoid cartilage and placing a plastic cannula and needle with fluid filled syringe attached into trachea. Aspiration of air confirms correct placement of the tip in the trachea. Next the needle is removed and the hollow cannula is left in place to enable insertion of a soft tipped guide wire into trachea through the bore of the hollow cannula. The cannula is removed leaving the guide wire in place and tracheal dilatation is undertaken using suitable means. Finally, after appropriate dilatation the tracheostomy tube is inserted with concomitant withdrawal of the endotracheal tube and ventilator tubing is connected.
Preferred dilatation procedures nowadays may follow the Ciaglia techniques, either using the Ciaglia Blue Dolphin or the Ciaglia Blue Rhino from Cook.
Ciaglia Blue Dolphin uses balloon dilatation. Ciaglia Blue Rhino is a single large tapered dilator with a soft, pliant tip and curved contours. The conical Ciaglia Blue Rhino dilator is advanced over a plastic guidewire reinforcement to enlarge the opening in the trachea. Both Ciaglia techniques are well reputed but can only be performed by very skilled staff. Moreover, they all include a plurality of steps before the tracheostomy procedure is finalised and the trach tube is placed properly. For further discussion of the known techniques for tracheostomy references are made to the applicant's International patent application no WO2007/018472.
When performing a percutaneous tracheotomy with all existing techniques, there is a risk of serious surgical complications e.g. damaging the posterior tracheal wall, large neck blood-vessels and fractures of tracheal rings.
Thus there is a need within the art for simple techniques for performing tracheostomy procedures fast and in a safe manner.
International patent application no. WO2008/09943 discloses a tracheostomy dilator for use with a guide wire in a single dilator step. This known tracheostomy dilator is curved along its length. Is has a tapering patient end region at one end and an oppositely curved handle region at its opposite end. A passage extends rearwardly along the dilator from its patient end and opens on a side of the dilator at an opening in the handle region. The passage is blocked rearwardly of the opening by an insert with a forward ramp surface, which directs a guidewire. In use one end of the guidewire projects from the patient end of the dilator and its opposite end extends along the outside of the handle region. Due to a.o. the prerequisite guide wire this known dilator cannot be used when the patient already has an endotracheal tube for ventilation. Such an endotracheal tube needs to be removed first at the risk of the patient is without respiration for the subsequent period while the tracheostoma is created. Moreover the tracheostomy dilator would take up considerable space if arranged next to an endotracheal tube and be difficult to maneuver without the endotracheal tube gets dislocated.
U.S. Pat. No. 3,511,243 discloses an apparatus for use in emergency tracheotomy, which apparatus suffers from some of the same and additional disadvantages as the above described tracheostomy dilator according to WO2008/09943. The apparatus comprises a flexible leader member for insertion through a hollow needle into the tracheal lumen, an expanding adapter apparatus detachably engaging one end of the leader member, said expanding adapter apparatus including an outer O-shaped tapered guide conduit member formed with an expanding slot and an inner expanding adapter element telescopically arranged in the outer guide conduit to extend outwardly therefrom, a cutting edge extending rearwardly from the outer guide conduit extremity. The expanding slot of the O-shaped tapered guide conduct is employed to hold a tube or other instrument in place by means of a tool inserted through the expandable slot while the O-shaped tapered guide conduit member is removed by means of a radially protruding handle the same way is was inserted. This known apparatus cannot be inserted if an endotracheal tube already is inserted in the trachea, a.o. due to the presence of the cutting edge that might damage the endotracheal tube, the large diameter of between one to one and a half inch, and the spatial hindrance if an endotracheal tube already is present.
An improved device for making a tracheotomy is known from the applicant's International patent application no. WO2007/018472. This device provides a novel surgical instrument assembly by means of which a tracheotomy can be made at lesser risk of complications and very fast. An endotracheal tube with an inflatable cuff close to the tip is inserted into the trachea. The cuff is inflated at the appropriate location just below larynx. A first branch of the instrument is guided into the trachea alongside the endotracheal tube leaving a second branch exterior to the patient and a part of the first branch inside the trachea. The second branch is hinged to the first branch at a distance from the tips of the branches, e.g. in a scissor-like or tweezer-like manner, enabling the tip of the second branch to be moved towards the tip of the first branch to puncture the neck tissue and the anterior wall of the trachea. The tip of the first branch may have a countermeasure or backstop, such as a stop plate, for preventing through puncture of the posterior tracheal wall when the tip of the second branch are swung towards the neck for penetration of the anterior tracheal wall and making the puncture. After successful puncture the second branch is swung aside and the first branch is removed from the trachea the same way it was inserted, namely through the mouth. Dilatation is then made and a tracheostomy tube is arranged into the dilated hole.
While this novel procedure discloses a plurality of advantageous feature over the prior art the inventor and applicant still aim for improving the surgical procedure towards simplified and safer techniques that can be made very fast. The faster respiration ability is restored the lower risk of brain damages. Faster and simpler procedures will save more lives.